The Chinese government says a dispute about alleged North Korean counterfeiting of U.S. dollars, and other illegal financial activities is delaying negotiations to end North Korea's nuclear programs.

The Chinese government has said it supports an investigation into U.S. allegations that North Korea is counterfeiting dollars and has also used a bank based in Macau, a special administrative region of China, as a front for illicit financial deals.

But at a regular briefing, Chinese Foreign Ministry spokesman, Kong Quan, said the charges are preventing a resumption of six-nation talks aimed at ending North Korea's nuclear programs.

"This issue has already become interference or an element of obstruction to the six-party talks process," he said. "China, as host, has continuously and actively mediated to urge North Korea and the U.S. to consult to find an appropriate solution."

The United States in September accused North Korea of counterfeiting and said the Banco Delta Asia bank in Macau was being used by Pyongyang for money laundering.

The United States has since imposed financial sanctions on the bank and several North Korean companies. Pyongyang says it will not return to six-nation negotiations aimed at ending its nuclear programs until the sanctions are lifted.

The United States is also urging South Korea to step up efforts to counter alleged illegal financial activities by North Korea.

South Korea has only said it will cooperate with international efforts against all financial crimes, but did not respond specifically to the U.S. allegations about North Korea.

But the South Korean government has urged Pyongyang to return to talks on its nuclear program in February without preconditions.

The six-nation negotiations have been stalled since November. In addition to China, the two Koreas and the United States, the talks include Japan and Russia.